Manufacture of shoes



sept. 4, 1934. N F HopKm-s 1,972,342

MANUFACTURE OF SHOES Filed Oct. 30. 1951 2 Sheets-Sheet 2 /NvE/WUR Patented Sept. 4, 1934 UNITED STATES MANUFACTURE 0F SHOES Nathan F. Hopkins, Rockland, Mass., assigner,

by mesne assignments, to

The Littleway Process Company, Boston, Mass., a corporation of Massachusetts Application October 30, 1931, Serial No. 572,103

17 Claims. (Cl. 12,-142) This invention relates to improvements in methods of manufacturing shoes and is illustrated herein with reference to the manufacture of a shoe the upper of which is secured in lasted relation to an insole by stitching and the sole of which is attached by cement.

It is an object of the present invention to provide a method of manufacturing shoes, applicable, though not limited in its utility, to use in the manufacture of shoes the soles of which are at-v tached by cement, of such a character that the Shanks and foreparts of the shoes shall be entirely free from metallic fastenings and the inner sur# faces of their insoles smooth and free from stitching, tack holes, etc.

A further object of the invention is to provide a shoe having a high degree of flexibility without sacrificing the light and trim appearance which is characteristic of many shoes the soles of which are cement attached.

In the illustrated shoesgmade in accordance with the method of my invention, the shoe upper is secured in lasted relation to the insole by` stitches each having a single thread lying on the overlasted marginal portion of the shoe upper close to the edge of the outsole, the marginal portion of the shoe upper being substantially flush with the bottom of the insole thereby providing a smooth shoe bottom for the reception of the outsole. This construction not only provides extreme flexibility but, if the outsole is cement attached, eliminates thenecessity for roughening the overlasted marginal portion of the shoe upper prior to the application of the cement, since the stitching can conveniently be located so near the edge of the sole that a thorough bond is obtained by cementing the outsole merely to the edge surface of the upper and the adjacent portion of the outsole.

In the manufacture of the illustrated shoes an insole having two substantially parallel Alips is used. ThisV may conveniently be prepared by channeling inwardly at the edge of the insole, the channel extending in from the edge of the insole about 1/8 of an inch or even a trifle less. A second or inner channel is formed extending peripherally of the insole and inclined downwardly into the substance of the insole so that its bottom is spaced a short distance from the outer channel thereby providing between-substance suitable for the reception of stitching. The two channels are opened to form a pair of substantially parallel lips. The insole is mounted on a last and the upper worked into lasted relation to the insole and the last, being secured in lasted relation by fastenings illustrated as staples passing' through the upper and the outer lip. The upper is then stitched to the insole by a seam the stitches of which each have a single thread lying cn the shoe upper close to the edge of the last so that the inseam may be trimmed close without danger of cutting the thread. The stitches, as *illustrated extendfthrough the between-substance at the base of the lips into the inner channel. After the stitching has been done the surplus marginal portion of the shoe upper and the outer lip are trimmed off between the line of staples and the stitching, thereby removing the staples and leaving the trimmed edge surface of the upper substantially flush with the bottom surface of the insole. The inner lip is returned to its original positionfbeing cemented down, if desired, preferably before the trimmingY operation, and the shoe bottom after trimming may be leveled, for example with an automatic leveler of the type commonly used in the manufacture 0f Goodyear welt shoes. K

An outsole is next attached, as illustrated by pyroxylin cement. It is not necessary to roughen the shoe bottom before the cementis applied, though a very light leuning of the marginal portion of the insole andthe edge surface of the upper may be performed if desired.` This is in direct contrast to the vigorous roughening operation performed on the overlasted marginal portion lof the shoe upper which has heretoforebeen typical of the manufacture of shoes the soles of which are attached by cement and which often weakens the shoe upper -to a serious extent. The marginal portion of the sole is roughened` and coated vwitli pyroxylin cement, which is allowed to dry in the usual fashion, after which it is cut with a suitable softener, the sole .and the shoe applied to keach other, and placed under pressure while the cement sets. -v As previously noted, the method of my invention produces a highly. flexible shoe the shank and forepart of which are free from metallic fastenings and the inner surface of the insole of which is free from stitching, tack holes, etc., and obvia-tes the-weakening of the overlasted portion of the shoe upper resulting from the usual roughening operation as well as saving the cost of that painstaking and relatively expensive operation. Further advantages comprise the economy following from'the saving of upper leather which results from the smaller lasting allowance neces-A sary as compared with thatrequired when the sole is to be cemented to the roughenedv upperjasis GDI usual in the manufacture of shoes having cement attached soles.

With the above and other objects in View the invention will now be described with reference to the accompanying drawings and pointed out in the claims.

In the drawings,

Fig. 1 is a transverse section of an insole which may be utilized in the manufacture of shoes in accordance with my improved method;

Fig. 2 is a sectional view showing the manner in which the upper of the shoe is secured by staples in lasted relation to a lip of the insole;

Fig. 3 is a similar view illustrating the securing of the upper to the insole by a chain-stitch seam, each of the stitches of which has a. single thread lying on the shoe upper;

Fig. 4 is a sectional View illustrating the use of a lockstitch seam, instead of a chain-stitch as in Fig. 3; Fig. 5 is a sectionalview illustrating the shoe after the surplus portion of the shoe upper and the -lipfof the insole have been trimmedoff thereby removingthe staples from the shoe;

Fig. 6 is a sectional view illustrating the leveling of the shoe bottom after the trimming operation;

Fig. '7 is a sectional view of an insole, similar to that vof Fig. 1 but illustrating an alternative method of channeling.;

Fig. 8 is a sectionalview of a .shoe made with the insole of Fig. 7 after the leveling Voperation and with its bottom ready for the attachment of the outsole;

Fig. 9 is a perspective view of a shoe, prepared as illustrated in Figs. 1 to 6, inclusive, showing also cement applied to the shoe bottom for the attachment of the outsole; d

Fig'. 10 is a perspective view of an outsole which is to beattached to the shoe of Fig. 9, and illustrating also the application-of cement-and softener to the outsole; and

Fig.. 1l is -a perspective view and Fig. 12 a sectional view of the shoe after its outsole has been attached.

In the manufacture of the illustrated shoe the insole 18 is fitted with two channels, a peripheral outer channel 20` (Fig. 1) formed by cutting inwardly from the edge of the insole and an inner channel 22 extending peripherally of the insole 'andinc'l'ined' from the bottom surface of the insole so that its bottom is spaced a short distance from the outer channel, thereby providing between-substance 24 suitable for the reception of stitching. The channel "flaps are raised from the surface .of the insole forming lips, as illustrated at 26, 28 in Fig. 1. 'I'he insole fitted in this manner is mounted on a last 30 (Fig. 2) in the usual way. The shoe upper 32 is assembled upon the last and pulled over in the usual manner and the upper 32 is then worked into lasted relation. VThe side lasting kmaybe performed with the aid of, for example, a side'lasting machine of the character illustrated in Letters Patent of the United Statesl No. 1,796,451, 'granted March 17, 1931 on an application filed in the name of George Goddu, staples 34 being inserted through the shoe upper and the outer lip 26 slightly above the base of the lip, as shown in Fig. 2. After the side lasting roperation the toe and the heel seat may be lasted with the aid of a bed lasting ma.- chine in the manner ordinarily used in the manufacture of Goodyear welt shoes.

The upper is next stitched to the insole. This may be done by' a chain-stitch, as illustrated at 36 in Fig. 3, or by a lockstitch, as illustrated at 38 in Fig. 4. In either case the stitches pass through the shoe upper 32 and the between-substance 24 substantially at or even slightly below the base of the lips 26 and 28, each stitch having a single thread 40 lying upon the shoe upper and pulling the upper close down into the angle at the base of the lip 26. If a chain-stitch is used, as shown in Fig. 3, it will have two threads 42 lying in the channel 20. For this seam a relatively ne thread and needle should be used, for example a 4-cord thread and a #45 needle. In case a vlockstitch is used each stitch will have only a single thread 44 in the channel 20 as well as a single thread 46 lying upon the shoe upper 32, as shown in Fig. 4, in which figure the ina- .terial of the shoe upper 32 and the outer lip 26 is illustrated in cross section better to show the lockstitch seam. This stitching, whether chainstitch or locksttch, lies between the row of staples 34 andthe marginalportion of the insole so that the surplus portion or lasting allowance 48 vof the upper and the lip 26 can be trimmed olf close to the seam, as illustrated in Fig, 5, leaving the edge surface 50 of the shoe upper substantially flush with the bottom 52 of the insole. While the insole is in temper following the stitching, and .preferably before the trimming operation, the flap or lip 28 may be laid back in the channel 22. While cement may be used to hold the i'iap in the channel, I believe it is better to leave the flap loose, thereby promoting the flexibility of the shoe andobviating any possibility of the channel cement affecting adversely the pyroxylin cement by which the outsole may be secured Ato the shoe.

After the trimming operation above described, which extends from substantially the heel breast line forwardly around the toe of the-shoe and back to the heel breast line at the other side,

the bottom of the shoe may be leveled, for example by means of a leveling machine of the automatic type commonly used in leveling the soles. of Goodyear welt shoes. This operation,

which is illustrated at 52 in Fig. 6, assures a' smooth flat bottom,- -as'shown in .that figure, for the reception of the outsole, the shoe after the leveling operation being substantially in the condition illustrated at the nearer side of Fig. 9. After the leveling operation the surface of the insole 18 adjacent to .the shoe upper yand the edge surface 50 of the shoe upper may be lightly buifed, if desired, to improve the surfacefor the reception of the pyroxylin cement which is presently to be applied. I do not regard this buiiing operation as essential, however, and if it is used the leveling operation may be omitted, though the latter is desirable if the best yresults are to be obtained. The buing just referred to should not remove any of the finished surface from the l upper leather 'and is not to be confused withthe vigorous roughening operation which is commonly performed upon the overlasted marginal portion of shoe uppers the soles of which are to be cement attached by the methods heretofore `in use. In the manufacture of shoes inaccordance with my invention it is preferable thatthe surface of the upper leather beyond the stitching should not be touched by the buffing operation, if such an operation is performed, since a secure cement attachment of the outsole is obtained without such unnecessary defacing or weakening operation.

If desired, the outer channel of the insole, instead of splitting the insole substantially parallel Mil toits bottom surface, as illustrated in Fig. 1, may extend diagonally inwardly (Fig. 7) from the corner 54 where the edge surface 56 and the bottom surface 58 meet. A shoe manufactured as previously described, but with an insole fitted as shown in Fig. '7, is illustrated in cross section in Fig. 8. This shoe prior to the attachment of its sole is generally similar to that of Fig. 6, the principal difference being that the very narrow overlasted marginal portion of the shoe upper is substantially flat, as indicated at 60 (Fig. 8), instead of being somewhat rolled sothat when the outsole is applied it will have a substantially flat bottom as distinguished from a rolled edge.

The shoe, whether made with the insole of Fig. 1 or with the insole of Fig. 7, is now ready for the attachment of its outsole. As illustrated, a coat of pyroxylin cement is applied, shown at 62 at the further side of Fig. 9, to the edge surface of the shoe upper and the adjacent portion of the bottom of the insole, care being taken that the cement is not spread upon the surface ofthe shoe upper beyond the stitching 40. This cement, which extends about the shank and forepart of the shoe from breast line to breast line, is allowed to dry in the usual fashion; The outsole, illustrated at 64 (Fig. 10)Y as prepared in the manner usual in the manufacture of shoes having cement attached soles, is intact in that it is Vfree from anything of the nature of a channel or groove, and its marginal portion is therefore of maximum strength for a given thickness and quality of leather. This intact condition of the outsole, moreover, is maintained in the finished shoe since the marginal portion of thev outsole is free from needle holes. Its'marginal portion may be, and, as illustrated at 66, is, reduced in thickness at the forepart and shank to' produce a light and trim edge appearance inthe finished shoe. The attaching surface of the sole 64 is roughened over an area extending peripherally of the sole from approximately the heel breast line forwardly about the toe of the shoe and rearwardly to the heel breast line at the other side, `as illustrated at 68. Pyroxylin cement, illustrated at '70, is applied to this roughened area and is allowed to dry. Preferably the cement does not extend entirely to the edge of the sole as indicated at 72, Fig. l0. This may be accomplished either by leaving an uncemented strip at the extreme marginal portion of theattaching face of the sole or the cement may be applied clear to the edge and thereafter removed fromthe extreme margin in any suitable way. kAfter the shoe and sole have been prepared in this fashion the cement on the sole, or on both the sole and the shoe bottom, is softened with a suitable softener, indicated at 74 (Fig. 10). The sole and the shoe are then applied to each other and placed under pressure, for example in the pad box of a cement sole attaching machine of the character disclosed in an application for Letters Patent of the United States No. 1,897,105, granted February 14, 1933, on an application filed in the naine of Milton H. Ballard, while the cement sets. When the shoe is removed from this machine it will have substantially the appearance illustrated in Fig. l1 and its bottom will have substantially the cross section illustrated in Fig. 12 in which the heavy line '76 represents diagrammatically the location of the cement by which the outsole 64 is secured to the edge surface 50 of the shoe upper and the adjacent portion of the bottom surface 52 of the insole 18. It should be noted also that this cement will cause the outsole to adhere to the thread 40 or 46 of the stitches provided the lubricating medium used on the thread is one which is not incompatible with pyroxylin.

In addition to the Various advantages previously mentioned resulting from the practice of my invention it may be noted at this time that it pro-- vides shoes having unusually smooth and dat bcttoms. The stitching 36 or 33 provides an attachment of the upper 32 to the insole 18 which is secure, is unexceeded in iiexibility by any known method of attachment, and promotes the ready repairability of the shoe. Moreover, it improves the quality of the lasting to a substantial extent because of the manner in Which it pulls the upper into the angle at the base of the outer lip 26.

The stitching 36, 38, moreover, whether chainstitch or lockstitch, does not provide sufficient bulk of material to interferewith the flat bottom of the shoe, though it is with this end in View that, if a chain-stitch is used, it is best inserted in such a manner that the single thread of each stitch lies on the shoe upper While the double thread lies in the inner channel 20, though even this arrangement of the stitching I do not regard as essential in all aspects of the invention since with the relatively ne thread which is adequate for this operation, the leveling prior to the attaching of the outsole compacts the parts of the shoe bottom into a smooth and substantially flat surface for the reception of the outsole. Moreover, with the outer lip of the insole close to the edge oi the insole and to the edge of the bottom of the last, as illustrated herein, the thread which engages the shoe upper is, in the finished shoe, so close to the edge of the sole that there is no necessity for extending the sole attaching cement beyond that thread, a secure attachment of the outsole being provided by cement applied to the edge surface of the shoe upper, to the adjacent surface of the Lisole, and even to the thread itself, instead of to the roughened grain surface of the upper leather as is the usual practice.

While the manufacture of shoes by the method of my invention has been described in some detail in the Yforegoing specication it should be borne in mind that it is susceptible of substantial variation without departing from the spirit of the in- Vention. Thus it is not essential under all circumstances that two channels and lips be provided. Also in some aspects of the invention it is not necessary that the upper be secured to the lip of the insole by staples before the stitching is inserted. Other variations in the process will be evident to persons skilled in the manufacture oi shoes. Moreover, while the shoe upper has been spoken of herein as leather it should be understood that this is merely as a matter or" convenience. The invention is applicable to the manufacture of shoes having uppers of other materials. such as Woven fabrics, and the claims should be so construed.

Having thus described my invention what I claim as new and desire to secure by Letters Patent of the United States is:

1. That improvement in methods oi manufacturing shoes which comprises mounting on a last an insole having a lip close to its edge, securing a shoe upper in lasted relation to the insole vby staples passing through the upper and the lip of the insole, thereafter securing the shoe upper to the insole by stitching passing through the upper and the substance of the insole with the thread of the stitches lying on the upper, trimming orf the lip and the surplus portion of the upper close to the stitching thereby removing said staples, and

" outsole by cement to the shoe bottom.

oli the surplus portion or theupper close kto attaching an outsole in contact with the edge surface ofthe upper and with the. surface of the insole adjacent thereto.

2. That improvement in methods ofmanufacturing shoes which comprises mounting-on a last an insole having a double lip close to its edge, Working an upper over the last into lasted relation to the lip, securing the upper temporarily in lasted position to the outer lip ony,'zperinanently secur.y

ing the shoe upper in lasted relation to the insole by stitching passing through vthe upper andthe substance of the insole at the base of the lip with the thread of the stitches lying on the shoe upper close to the edge or" the last bottom,` trimming orf the lip and the temporarily secured portion oi the upper close to the stitching, and attaching an outsole in contact With the edge surface oi the upper and with the surface of the insole adjacent thereto.

3. That improvement in methods of `rnariuiacn turing shoes which comprises securing a shoe upper in lasted relationto a lipped insole mounted on a last by staples inserted throughthe manginal portion oi the upper and the lip of the insole,

x securing the upper and the .insole together by stitching passing through the upper and the sube stance of the insole at the base-oi' ,the lip, trimming oi the lip and the surplus portion or the upper including the staples,A attaching an Ll. That improvement in methods of manufacturing shoes which comprises Working a yshoe upper into lasted relation to an insole mounted on a last, securing the upper in lasted relation to the insole by staples passing thro-ugh the upper and into the insole Without penetrating to the last'- engaging surface of the insole, ksecuringthe upper to the insole by stitching, each stitch of which has a single thread lying on the shoe upper, trimming the stitching thus removing the staples, leveling the shoe bottom, and securing an outsole in Contact with the trinuned edge surface Aoi the shoe upper and the adjacent surface oi the insole.

5. That improvement inmethods of manufacturing shoes which comprises Working a shoe upper into lasted relation toa lipped insole mounted on a last, securing the upper in lasted relation by staples inserted through the marginal portion of the upper and the lip of the insole, securing the upper and the insole together by stitches passing through the upper and into the insole at the base of the lip, trimming oi the lip and the surplus portion of the upper including the staples, and cement attaching4 an oui'soleto the` shoe.l k p 6. That improvement in methods of manufacturing shoes which comprises Working a kshoe upper into lasted relation vto a lipped insole mounted on a last, securingthe upper in lasted relation by staples inserted through the marginal portion ci the upper and the lip or" the insole, securing the upper and the insole togetherby stitching passing through the upper and into the substance or the insole substantially at the base of the lip, trimming oi the lip and the surplus portion oi the including the staples, levels ing the shoe bottoni, and thereafter cement attaching an outsole to the shoe. 1 y,

'7. That improvement in methods oi .manufacturing shoes Which comprises securing shoe upper in lasted relation to a lipped insole rnountv ed on a last by staples inserted-through the nal portion of the upper and the lip of the insole, securing the upper andthe insole together by chain-stitching passing` through the upper and the substance of the=insole substantially at the base of the,lip,each stitch having. a. single thread.

stancel of the insole at the base of the lip with the thread of thestitches lying on the shoe upper close to the edge ofthe last, trimming ofi the lip and thesurplus portion of the upper including the staples, leveling .the shoe bottom,l and attachingy an outsole byl cement to the edge ,surface of the upper and to the surface of the insole adjacent thereto. v v

Y 9.V That improvement in methods of manufacturing shoes vWhich comprises securing. a shoe upper in lasted relation to a lipped insole mounted on a last by staples `inserted through the marginalportion ofthe upper and the lipof `the insole; securing the upper and the insole together by stitching passing ,through the upper and the substance of the insole at the base of the lip with the threads of the stitches lying on the shoe upper' closeto the edge of the last,ftrimming off the lip and the surplus portion of the upper closev to the stitching-leveling the shoe bottom, and attaching anoutsole by cement to the 'edgesurface of the upper and to the surface of the insole'adjacent thereto. f.

l0. That improvement in methods of. manufacturing shoes which comprises securing a. shoe upper in lasted relation to a. lipped insoleV mounted on a last by staples inserted through the marginal portion of the `upper and the lip'of the insole, securing the upper andthe insole together by stitching passing through the upper and the'substance ofthe insole atrthe base of the lip, each stitch having a single thread lying on the shoe upper, trimming 01T the lip and the surplus portion of the upper, and cement attaching an .outsoleto the shoe bottom.

11. That improvement in methods of manufacturing shoes Which comprises securing a shoe upper in `lasted relation to an insole having a. pair of peripherally extending lips 'by staples inserted through the marginal portion of the upper and through atleast the outer lip ofthe insole, securing the upper and the insole together by stitching passing through the upper` and the'betweensubstance atthe base of the lips of the insole, trimming-off vat least the outer lip and the surplus-portion of the insoleA including the staples close to the stitching, leveling Ythe -shoe bottom, and attaching an outsole by cement to the shoe bottom. l 12. That improvement in methods of manufacturing shoes which comprises securing a shoe upper in lasted relation to an insole having a pair of peripherally extending lips by staplesV inserted through the marginal portion of the upper and the` outer lip of the insole, securing the upper and the, insole together by stitching passing through the upper and the between-substance at the-baseof vthe lips of the insole, trimming off the outer lip and the surplus portion of the upper including the staples, cementing the inner lip back in its original position, leveling the shoe bottom, and attaching an outsole by cement to the edge surface of the upper and to the surface of the insole adjacent thereto.

13. That improvement in methods of manufacturing shoes which comprises securing a shoe upper in lasted relation to an insole having a pair of peripherally extending lips by staples inserted through the marginal portion of the upper and the outer lip of the insole, securing the upper and the insole together by stitches passing through the upper and the between-substance at the base of the lips of the insole, each stitch having a single thread lying on the shoe upper, trimming off the outer lip and the surplus portion of the insole including the staples, returning the inner lip to its original position and leveling the shoe bottom, and attaching an outsole by cement to the edge surface of the upper and to the surface of the insole adjacent thereto.

14. That improvement in methods of manufacturing shoes which comprises channeling inwardly a short distance from the edge of the insole, forming an inner channel extending peripherally of the insole at an inclination to the bottom of the insole, opening the two channels thereby forming a pair of substantially parallel lips the outer of which is close to the edge of the insole, mounting the insole on a last, Working a shoe upper into lasted relation to the insole and last, securing the upper to the insole by stitching passing through the upper and the between-substance of the insole substantially at the bases of the lips, each stitch having a single thread lying on the shoe upper, trimming off the outer lip and the surplus portion of the shoe upper asclose to the stitches as the single thread will permit, and attaching an outsole in contact with the edge surface of the shoe upper and the adjacent surface of the insole.

15. That improvement in methods of manufacturing shoes Which comprises forming an outer lip by channeling inwardly from the edge of an insole, forming an inner lip extending peripherally of the insole substantially parallel to the rst by channeling at an inclination to the bottom of the insole, mounting the insole on a last, working a shoe upper into lasted relation to the insole and last, preliminarily securing the upper in lasted relation to the insole by staples inserted through the upper and the outer lip, securing the upper to the insole by stitching passing through the upper and the between-substance of the insole substantially at the bases of the lips, trimming oi close to the stitches the outer lip and the surplus portion of the shoe upper including the staples, and attaching an outsole in contact with the edge surface of the shoe upper and the adjacent surface of the insole.

16. That improvement in methods of manu-V the upper and the between-substance of the insole substantially at the bases of the lips, trimming off the outer lip and the surplus portion of the shoe upper close to the stitches, the staples being thereby removed, and attaching an outsole in contact with the edge surface of the shoe upper and the adjacent surface of the insole.

17. That improvement in methods of manufacturing shoes Which comprises reducing the marginal thickness 0I" an insole by channeling inwardly from the edge of the insole at a distance from the bottom surface of the insole not greater than the thickness of a shoe upper, forming an inner channel extending peripherally of the insole at an inclination to the bottom of the insole with its base spaced a short distance from the base of the other channel, opening the two channels thereby crming a pair of substantially parallel lips, mounting the insole on a last, Working a shoe upper into lasted relation to the insole and last, securing the upper in lasted relation to the insole by staples inserted through the marginal portion of the upper and the outer lip of the insole, thereafter securing the upper to the insole by stitching passing through the upper and the between-substance of the insole at or beneath the bases of the lips, trimming off the outer lip and the surplus portion'or" the shoe upper adjacent to the stitches and thereby removing the staples, leveling the shoe bottom and attaching an outsole by cement to the edge surface of the shoe upper and the adjacent surface of the insole.

NATHAN F. HOPKINS. 

